It is critical for Day traders to know which currencies are strong and which one are weak when trading the Forex market.
This strength or weaknesses could be as result of short term demand and supply but can also be caused by economic announcement results.
Ideally one should always trade the strongest currency against the weakest currency.
Use the Forex Trading currency tools below to select a timeframe and currencies to view
Other sources of relative strength of currency information
FX Street provides heatmaps of currencies.
Use this link or click on the picture for more information: http://www.fxstreet.com/technical-studies/currencies/heat-map/